Polymeric fibers, such as nanofibers, have a broad array of uses including, but not limited to, use in catalytic substrates, photonics, filtration, protective clothing, cell scaffolding, drug delivery and wound healing. Structures prepared using polymeric fibers are good candidates for tissue engineering because such structures can be easily wound into different shapes, have a high surface to mass ratio, high porosity (which contributes to breathability), ability to encapsulate active substances, and the ability to be aligned, and the like. Tissue engineering applications for structures made using polymeric fibers may include, but are not limited to orthopedic, muscular, vascular and neural prostheses, and regenerative medicine. Madurantakam, et al. (2009) Nanomedicine 4:193-206; Madurantakam, P. A., et al. (2009) Biomaterials 30(29):5456-5464; Xie, et al. (2008) Macromolecular Rapid Communications 29:1775-1792.
Electrospinning is a conventional process for fabricating polymeric fibers. Electrospinning uses high voltages to create an electric field between a droplet of polymer solution at the tip of a needle and a collection device. One electrode of the voltage source is placed in the solution and the other electrode is connected to the collection device. This exerts an electrostatic force on the droplet of polymer solution. As the voltage is increased, the electric field intensifies, thus increasing the magnitude of the force on the pendant droplet of polymer solution at the tip of the needle. The increasing electrostatic force acts in a direction opposing the surface tension of the droplet and causes the droplet to elongate, forming a conical shape known as a Taylor cone. When the electrostatic force overcomes the surface tension of the droplet, a charged continuous jet of polymer solution is ejected from the cone. The jet of polymer solution accelerates towards the collection device, whipping and bending wildly. As the solution moves away from the needle and toward the collection device, the jet rapidly thins and dries as the solvent evaporates. On the surface of the grounded collection device, a non-woven mat of randomly oriented solid polymeric fibers is deposited. Zufan (2005) Final RET Report; Xie, J. W. et al. (2008) Macromolecular Rapid Communications 29(22):1775-1792; Reneker, D. H., et al. (2007) Advances in Applied Mechanics 41:43-195; Dzenis, Y. (2004) Science 304(5679):1917-1919; Rutledge, G. C. and Yu, J. H. (2007) “Electrospinning” In Encyclopedia of Polymer Science and Technology, John Wiley & Sons: New Jersey; Krogman, K. C., et al. (2009) Nature Materials 8(6):512-518; Pham, Q. P., et al. (2006) Tissue Engineering 12(5):1197-1211; Boland, E. D., et al. (2001) Journal of Macromolecular Science-Pure and Applied Chemistry 38(12):1231-1243; Teo, W. E. and Ramakrishna, S. (2006) Nanotechnology 17(14):R89-R106; Li, D.; Xia, Y. N. (2004) Advanced Materials 16(14):1151-1170; Greiner, A. and Wendorff, J. H. (2007) Angewandte Chemie-International Edition 46(30):5670-5703.
There are multiple drawbacks associated with electrospinning, e.g., a low production rate, the requirement of a high voltage electrical field, the requirement of precise solution conductivity, and the need for additional devices for producing aligned fiber structures. Lia and Xia (2004) Advanced Materials 16:1151-1170; Weitz, et al. (2008) Nano Letters 8:1187-1191; Arumuganathar, S. and Jayasinghe, S. N. (2008) Biomacromolecules 9(3):759-766.
Accordingly, there is a need in the art for improved systems, devices and methods for the fabrication of polymeric fibers, such as nanofibers.